login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A252609 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 8 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 8 1
1051, 1379, 2817, 5304, 14435, 37917, 75859, 213611, 599753, 1195427, 3451701, 10095479, 19984819, 58655670, 176140167, 346827424, 1029346845, 3144314768, 6169315363, 18442681353, 56943954915, 111477238107, 334759247526 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A252615

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 37*a(n-3) -445*a(n-6) +2151*a(n-9) -4973*a(n-12) +7261*a(n-15) -8366*a(n-18) +5776*a(n-21) -1440*a(n-24) for n>33

EXAMPLE

Some solutions for n=4

..1..2..2..1....2..3..0..2....0..3..2..3....3..3..2..0....2..3..3..2

..0..2..3..3....2..1..2..2....1..2..2..1....1..2..2..1....2..1..2..2

..3..3..2..0....0..3..2..0....0..2..3..0....3..2..3..0....0..3..2..0

..1..2..2..1....2..3..0..2....0..3..2..0....3..0..2..3....2..3..0..2

..0..2..3..3....2..1..2..0....1..2..2..1....1..2..2..1....2..1..2..2

..0..3..2..3....3..3..0..0....3..2..3..3....3..2..0..3....3..0..2..3

CROSSREFS

Sequence in context: A204753 A252391 A020389 * A185680 A191858 A090005

Adjacent sequences:  A252606 A252607 A252608 * A252610 A252611 A252612

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 19 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 16 20:36 EDT 2021. Contains 348047 sequences. (Running on oeis4.)